CLUSTER_HARDWARE

The CLUSTER_HARDWARE hardware system table provides the hardware information of the server where each instance of the cluster is located.

USE information_schema;
DESC cluster_hardware;

+-------------+--------------+------+------+---------+-------+
| Field       | Type         | Null | Key  | Default | Extra |
+-------------+--------------+------+------+---------+-------+
| TYPE        | varchar(64)  | YES  |      | NULL    |       |
| INSTANCE    | varchar(64)  | YES  |      | NULL    |       |
| DEVICE_TYPE | varchar(64)  | YES  |      | NULL    |       |
| DEVICE_NAME | varchar(64)  | YES  |      | NULL    |       |
| NAME        | varchar(256) | YES  |      | NULL    |       |
| VALUE       | varchar(128) | YES  |      | NULL    |       |
+-------------+--------------+------+------+---------+-------+
6 rows in set (0.00 sec)

Field description:

• TYPE: Corresponds to the TYPE field in the information_schema.cluster_info table. The optional values are tidb, pd, and tikv.
• INSTANCE: Corresponds to the INSTANCE field in the information_schema.cluster_info cluster information table.
• DEVICE_TYPE: Hardware type. Currently, you can query the cpu, memory, disk, and net types.
• DEVICE_NAME: Hardware name. The value of DEVICE_NAME varies with DEVICE_TYPE.
  • cpu: The hardware name is cpu.
  • memory: The hardware name is memory.
  • disk: The disk name.
  • net: The network card name.
• NAME: The different information names of the hardware. For example, cpu has two information names: cpu-logical-cores and cpu-physical-cores, which respectively mean the number of logical cores and the number of physical cores.
• VALUE: The value of the corresponding hardware information, such as the disk volume and the number of CPU cores.

The following example shows how to query the CPU information using the CLUSTER_HARDWARE table:

SELECT * FROM cluster_hardware WHERE device_type='cpu' AND device_name='cpu' AND name LIKE '%cores';

+------+-----------------+-------------+-------------+--------------------+-------+
| TYPE | INSTANCE        | DEVICE_TYPE | DEVICE_NAME | NAME               | VALUE |
+------+-----------------+-------------+-------------+--------------------+-------+
| tidb | 0.0.0.0:4000    | cpu         | cpu         | cpu-logical-cores  | 16    |
| tidb | 0.0.0.0:4000    | cpu         | cpu         | cpu-physical-cores | 8     |
| pd   | 127.0.0.1:2379  | cpu         | cpu         | cpu-logical-cores  | 16    |
| pd   | 127.0.0.1:2379  | cpu         | cpu         | cpu-physical-cores | 8     |
| tikv | 127.0.0.1:20165 | cpu         | cpu         | cpu-logical-cores  | 16    |
| tikv | 127.0.0.1:20165 | cpu         | cpu         | cpu-physical-cores | 8     |
+------+-----------------+-------------+-------------+--------------------+-------+
6 rows in set (0.03 sec)